O.Thetford, P.Gray German Aircraft of the First World War (Putnam)

D.F.W. Dr I Photographed at Adlershof in January 1918, at the first D types Competition, was this triplane variant of the D I. which stands behind it. Engine, 160 h.p. Mercedes D III. Armament, twin Spandau machine-guns.

W.Green, G.Swanborough The Complete Book of Fighters

DFW T 34-II Germany

Evolved in parallel with the T 34-I biplane, the T 34-II (sometimes referred to erroneously as the Dr I) single-seat triplane employed a similar fuselage, power plant (Mercedes D III), armament (twin synchronised LMG 08/15s) and undercarriage to those of the biplane fighter. Both top and bottom wings were one-piece units mounted well clear of the fuselage and sufficiently staggered to obviate the need for a pilot-vision cut-out. The central wing carried generous ailerons and possessed broad tips, and the tail surfaces were similar to those of the definitive T 34-I, but incorporating a somewhat larger rudder. Together with the T 34-I, the T 34-II triplane was submitted for evaluation in the first D-type contest, but was excluded from the competition flight testing for reasons of poor pilot visibility and "unsuitable design”. No data on the T 34-II are available.